Vodivost tekoucích polyanilínových suspenzí v elektrickém poli

Abstract

V práci byla studována tvorba řetízkových struktur polarizovaných částic polyanilínu dispergovaných v silikonovém oleji při působení elektrického pole prostřednictvím monitorování časové závislosti vodivosti suspenze.

The formation of chain structures by polarized polyaniline (PANI) particles suspended in silicone oil in the electric field has been monitored by recording suspension conductivity in the course of time. For that purpose, three types of PANI particles differing in the conductivity (3.1 × 10?3, 1.7 × 10?1, and 2.0 × 10?1 S cm?1) have been chosen out of a series of nine samples prepared by controlled protonation of PANI base in orthophosphoric acid solutions. Relaxation times reflecting this process and characterizing the rate of the response to the electric field decreased with particle conductivity, indicating a higher polarizability of particles. At the same time, the maximum conductivity of suspension increased as a consequence of the electric and shear forces acting on the particles. In the shear fields, shorter relaxation times appeared than at rest. The simultaneous measurement of the shear stress confirmed that the conductivity investigation can reliably characterize the development of electrorheological structures.